Wheel bracket assemblies, which include a wheel bracket and a wheel rotatably supported on the bracket, are utilized in many applications, for example on shopping carts. In applications of this type, the wheel bracket assembly is frequently subjected to rough treatment and therefore must be durable and reliable. However, in industries which are highly competitive, it is also important that the wheel bracket assembly be relatively inexpensive in order to minimize the overall cost of the final product.
One conventional wheel bracket assembly used in applications of this type includes a U-shaped horn with the wheel rotatably supported between its legs, and a pin which is riveted in an opening in the bight of the horn and has transverse holes drilled therethrough (see FIG. 14). Although this conventional arrangement has been adequate for its intended purposes, it has not been satisfactory in all respects. In particular, several separate manufacturing steps are required to fabricate the wheel bracket, thus making the wheel bracket assembly relatively expensive. Further, the connection between the pin and horn is subjected to relatively large stresses and frequently tends to loosen over a period of time.
A further consideration is that it is usually desirable for a wheel bracket assembly of the foregoing type to have a small amount of pivoting and shock-absorbing capability when mounted on a shopping cart or other device, in order to minimize the stresses applied to the bearings. However, conventional arrangements which provide limited pivoting and/or shock-absorbing capability typically involve increased structural complexity of the wheel bracket assembly and thus an increased number of manufacturing steps to fabricate the wheel bracket assembly.
A further consideration is that, although the bearing in wheel bracket assemblies of the foregoing type are typically designed so that the lubrication applied to the bearings at the factory will last the useful lifetime of the device, situations sometimes arise in which additional lubrication is necessary. In conventional wheel bracket assemblies, further lubrication has typically required that the wheel bracket assembly be disassembled, the wheel lubricated, and the wheel bracket assembly then reassembled. This is a relatively expensive procedure, and its cost can frequently approach or exceed the cost of a new wheel bracket assembly thus making relubrication economically impractical.
Accordingly, an object of the present invention is to provide a wheel bracket assembly which is simple in structure and is relatively simple and inexpensive to manufacture.
A further object of the invention is to provide a wheel bracket assembly, as aforesaid, which can be fabricated with a minimum number of steps and with a minimal amount of labor.
A further object of the invention is to provide a wheel bracket assembly, as aforesaid, which is rugged and durable and requires no maintenance over its useful lifetime.
A further object of the invention is to provide a wheel bracket assembly, as aforesaid, which has an aesthetically pleasing appearance and preferably a somewhat streamlined shape.
A further object of the invention is to provide a wheel bracket assembly, as aforesaid, which has a small amount of pivoting and/or shock-absorbing capability when mounted on a shopping cart or similar vehicle.
A further object of the invention is to provide a wheel bracket assembly, as aforesaid, which includes a structurally simple arrangement for gaining access to the sealed bearing of the wheel in order to facilitate lubrication of the bearing in the unlikely event that lubrication should become necessary at some time during the useful life of the bearing.